The present invention relates generally to hitch systems for coupling a trailer or draft vehicle to a tow vehicle. More specifically, the present invention relates to a unitary, winch-driven hitch assembly which may be pivotally mounted to a tow vehicle rear.
A wide variety of hitch devices are proposed in the prior art known for coupling an object to a tow vehicle. For example, it is known to provide a trailer coupling with a manual or motorized winch to assist coupling of large or heavy loads. Representative of such winch-assisted hitches are the following U.S. Pat. Nos.: Adams, Pat. No. 2,170,983, issued Aug. 29, 1939; Atkins Pat. No. 3,345,082, issued Oct. 3, 1967; Pat. No. 3,596,925, issued Aug. 3, 1971 to Richie; Pat. No. 3,761,113 issued to Smitherman on Sept. 25, 1973; Christopher Pat. No. 3,848,895 issued Nov. 19, 1974; Pat. No. 4,127,295 issued Nov. 28, 1978 to Robinson; Pat. No. 4,466,632 issued to DeVorak on Aug. 21, 1984; and, Belcher, Pat. No. 4,807,899, issued Feb. 28, 1989.
The hitch assembly disclosed in the Belcher '899 patent comprises a tubular hitch receptacle associated with a motorized winch which is bolted to the tow vehicle. The winch cable extends through the hitch receptacle and is removably coupled to an elongated hitch bar configured to conform to the interior of the hitch receptacle. The hitch bar terminates in a hitch ball or other connector coupled to the trailer In operation, the hitch bar is first linked to the draft vehicle. The cable is connected to the hitch bar, and the tongue or hitch element of the draft vehicle is then drawn by the winch into alignment with the hitch receptacle. A locking pin automatically drops into position to lock the hitch bar within the hitch receptacle.
Although the aforementioned and related prior art winch-driven assemblies greatly assist in drawing a large or bulky load into registration with the hitch, there are certain disadvantages associated with their use. For example, the winch and hitch receptacle are generally mounted as separate units. Motorized winches are typically bulky, unsightly, and generally interfere with other uses of the tow vehicle. Hand-driven winches such as that shown in the DeVorak '632 patent also typically require a great deal of additional material for complex linkages to facilitate operation of the winch crank remotely from the hitch.
A further disadvantage experienced with prior art hitches is that once mounted, such assemblies cannot be conveniently removed when needed for use on other vehicles or for other purposes. There are many situations in which it would be very useful to remove the hitch assembly from the tow vehicle and mount it to another vehicle or to a stabilized object such as a pier or a building. For example, if the tow vehicle were disabled in a ravine or the like, it would be of great benefit to remove the hitch from the tow vehicle and mount it to an operative vehicle which could then tow the disabled vehicle to safety. Or in the event it were desired to move a boat or other large object into a workshed, for example, it would be beneficial to remove the hitch from the tow vehicle and mount it to the floor or a stable object within the workshed. This would be very difficult to achieve with the use of the prior art hitches, which are typically at least partially welded in place. However, no prior art hitch known to me is so configured and/or mounted to permit convenient removal when desirable.
More importantly, prior art winch-type hitches require the operator to first generally align the trailer tongue or draft vehicle with the hitch on the tow vehicle in order to prevent undue stress on the winch during operation. Unfortunately, with most prior art hitches known to me, if the draft vehicle is positioned at a sharp angle relative to the center of the hitch, the cable may break or the winch motor may become overloaded. Many situations can be presented in which such a hitch might be of use, if not for the inability to obtain general alignment of the hitch elements on the tow and draft vehicles prior to hitching. For example, it may occur that the vehicle or object to be towed is located downhill below the tow vehicle, such as in a ravine alongside the highway. In another situation, the trailer may be positioned in a limited access area through which a tow vehicle such as a large truck cannot be easily maneuvered.
Various prior art hitch units known to me provide flexible hitch members which may be selectively directed from side to side to reach the tongue of a trailer or other draft vehicle. For example, Allen U.S. Pat. No. 4,042,254 issued Aug. 16, 1977 discloses a conical hitch housing comprising a flexible chain or cable which draws the hitch member of the draft vehicle into proper registration with the housing.
The retractable hitch assembly taught by Tate, U.S. Pat. No. 3,738,683, issued June 12, 1973, comprises a hitch receptacle mounted upon a flexible steel which may be selectively extended or retracted from a rigid bumper-mounted housing. The spring may be extended in various directions to conveniently reach the hitch of a draft vehicle. A locking pin is provided to lock the retracted receptacle within the housing for transport. The hitch elements of the tow and draft vehicles must be pulled into general alignment before the hitch can be locked. Use of this particular hitching element requires substantial physical strength and effort by the operator. Moreover, its use involves certain safety hazards, since the operator must handle the hitch elements during hitching and alignment and manually lock the hitch when a coupling is achieved.
U.S. Pat. No. 4,178,011 issued Dec. 11, 1979 to Kirsch illustrates a hitch comprising a pair of cooperating conical members. The male hitch member associated with the tow vehicle is pivotally secured to a conventional bumper-mounted ball hitch, so that it can be pivoted to align with the female hitch member permanently mounted to the trailer. A screw-driven chain draws the hitch members into registration for coupling. The device requires a special mounting to be permanently installed on the draft vehicle, and cannot be readily removed for use on another vehicle. Moreover, its use is somewhat cumbersome and involves risk to the operator, since the chain is manually driven and the operator must position himself between the vehicles to effectuate a coupling. Finally, the Kirsch '011 hitch is incapable of a wide range of pivotal movement, since the male element must be initially generally aligned with the female in order to obtain a reasonable fit.
Putnam U.S. Pat. No. 4,125,272 issued Nov. 14, 1978 discloses a pivotal hitch. The hitch comprises an elongated, rigid hitch arm pivotally coupled to a conventional body-mounted trailer hitch. The hitch arm may be pivoted to register with a rigid tubular female member permanently mounted to the trailer tongue. A lock pin drops into a locking orifice when proper penetration and alignment is achieved. While greater flexibility is afforded with the device of the '272 reference, the device requires modification of the standard ball hitch of trailers to permanently attach the female member. Thus it is difficult to easily use the hitch with other than the selected draft vehicle.
In addition, there is no provision in the latter-mentioned '272 reference for use of a winch for drawing heavy or large tow loads. Finally, although a greater range of hitch movement is provided, it is necessary that at least general alignment of the vehicle be initially achieved since the hitch arm is short and must physically contact the female member to initiate coupling.